I have been migrating my company's mails to Office365. Everything was fine. But I just faced something I don't know how to solve.
After migrating a specific account, it contacts are shown as "UPN: email@example.com" . It causes an error, when send to this contact. "invalid recipient address".
Tried to find a similar situation, but i couldn't.
I'm new in the IT departament and its the first time I have contact with AzuraAD or Office 365.